Are There Some Games You’ll Never Get Rid Of?

We all like video games (I would hope). We all have our favorite games, favorite moments, and games that we've lost, traded or given away, for whatever reason. But are there games that you won't ever let go of? Games that would just tear you up inside if you discovered that you had misplaced it or lost it? Default Prime's Kyree Leary has a few, but he wants to know if you do too. And why.
(Culture, Golden Sun, Kingdom Hearts, okami, Pokemon Yellow, Retro, Super Smash Bros. Melee)